2 * Copyright (C) 2007 Red Hat. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
20 #include <linux/string.h>
21 #include <linux/xattr.h>
22 #include <linux/posix_acl_xattr.h>
23 #include <linux/posix_acl.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
28 #include "btrfs_inode.h"
31 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
33 static struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
38 struct posix_acl *acl;
40 acl = get_cached_acl(inode, type);
41 if (acl != ACL_NOT_CACHED)
46 name = POSIX_ACL_XATTR_ACCESS;
48 case ACL_TYPE_DEFAULT:
49 name = POSIX_ACL_XATTR_DEFAULT;
55 size = __btrfs_getxattr(inode, name, "", 0);
57 value = kzalloc(size, GFP_NOFS);
59 return ERR_PTR(-ENOMEM);
60 size = __btrfs_getxattr(inode, name, value, size);
62 acl = posix_acl_from_xattr(value, size);
65 set_cached_acl(inode, type, acl);
68 } else if (size == -ENOENT || size == -ENODATA || size == 0) {
69 /* FIXME, who returns -ENOENT? I think nobody */
71 set_cached_acl(inode, type, acl);
79 static int btrfs_xattr_acl_get(struct dentry *dentry, const char *name,
80 void *value, size_t size, int type)
82 struct posix_acl *acl;
85 acl = btrfs_get_acl(dentry->d_inode, type);
91 ret = posix_acl_to_xattr(acl, value, size);
92 posix_acl_release(acl);
98 * Needs to be called with fs_mutex held
100 static int btrfs_set_acl(struct btrfs_trans_handle *trans,
101 struct inode *inode, struct posix_acl *acl, int type)
109 ret = posix_acl_valid(acl);
116 case ACL_TYPE_ACCESS:
117 mode = inode->i_mode;
118 name = POSIX_ACL_XATTR_ACCESS;
120 ret = posix_acl_equiv_mode(acl, &mode);
123 inode->i_mode = mode;
127 case ACL_TYPE_DEFAULT:
128 if (!S_ISDIR(inode->i_mode))
129 return acl ? -EINVAL : 0;
130 name = POSIX_ACL_XATTR_DEFAULT;
137 size = posix_acl_xattr_size(acl->a_count);
138 value = kmalloc(size, GFP_NOFS);
144 ret = posix_acl_to_xattr(acl, value, size);
149 ret = __btrfs_setxattr(trans, inode, name, value, size, 0);
154 set_cached_acl(inode, type, acl);
159 static int btrfs_xattr_acl_set(struct dentry *dentry, const char *name,
160 const void *value, size_t size, int flags, int type)
163 struct posix_acl *acl = NULL;
165 if (!is_owner_or_cap(dentry->d_inode))
168 if (!IS_POSIXACL(dentry->d_inode))
172 acl = posix_acl_from_xattr(value, size);
176 } else if (IS_ERR(acl)) {
181 ret = btrfs_set_acl(NULL, dentry->d_inode, acl, type);
183 posix_acl_release(acl);
188 int btrfs_check_acl(struct inode *inode, int mask)
190 struct posix_acl *acl;
193 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
198 error = posix_acl_permission(inode, acl, mask);
199 posix_acl_release(acl);
206 * btrfs_init_acl is already generally called under fs_mutex, so the locking
207 * stuff has been fixed to work with that. If the locking stuff changes, we
208 * need to re-evaluate the acl locking stuff.
210 int btrfs_init_acl(struct btrfs_trans_handle *trans,
211 struct inode *inode, struct inode *dir)
213 struct posix_acl *acl = NULL;
216 /* this happens with subvols */
220 if (!S_ISLNK(inode->i_mode)) {
221 if (IS_POSIXACL(dir)) {
222 acl = btrfs_get_acl(dir, ACL_TYPE_DEFAULT);
228 inode->i_mode &= ~current_umask();
231 if (IS_POSIXACL(dir) && acl) {
232 struct posix_acl *clone;
235 if (S_ISDIR(inode->i_mode)) {
236 ret = btrfs_set_acl(trans, inode, acl,
241 clone = posix_acl_clone(acl, GFP_NOFS);
246 mode = inode->i_mode;
247 ret = posix_acl_create_masq(clone, &mode);
249 inode->i_mode = mode;
252 ret = btrfs_set_acl(trans, inode, clone,
256 posix_acl_release(clone);
259 posix_acl_release(acl);
264 int btrfs_acl_chmod(struct inode *inode)
266 struct posix_acl *acl, *clone;
269 if (S_ISLNK(inode->i_mode))
272 if (!IS_POSIXACL(inode))
275 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
276 if (IS_ERR(acl) || !acl)
279 clone = posix_acl_clone(acl, GFP_KERNEL);
280 posix_acl_release(acl);
284 ret = posix_acl_chmod_masq(clone, inode->i_mode);
286 ret = btrfs_set_acl(NULL, inode, clone, ACL_TYPE_ACCESS);
288 posix_acl_release(clone);
293 const struct xattr_handler btrfs_xattr_acl_default_handler = {
294 .prefix = POSIX_ACL_XATTR_DEFAULT,
295 .flags = ACL_TYPE_DEFAULT,
296 .get = btrfs_xattr_acl_get,
297 .set = btrfs_xattr_acl_set,
300 const struct xattr_handler btrfs_xattr_acl_access_handler = {
301 .prefix = POSIX_ACL_XATTR_ACCESS,
302 .flags = ACL_TYPE_ACCESS,
303 .get = btrfs_xattr_acl_get,
304 .set = btrfs_xattr_acl_set,
307 #else /* CONFIG_BTRFS_FS_POSIX_ACL */
309 int btrfs_acl_chmod(struct inode *inode)
314 int btrfs_init_acl(struct btrfs_trans_handle *trans,
315 struct inode *inode, struct inode *dir)
320 #endif /* CONFIG_BTRFS_FS_POSIX_ACL */